Fig. 8

Estimations of aboveground biomass (AGB) at different growth stages by random forest (RF) model using the combination of nine vegetation indices (VIs) and canopy height derived from crop surface model (Hcsm) (a). Estimation of biomass developed by RF model using single variable with four growth stages (b). The r², RMSEP and RRMSE represent the coefficient of determination, the prediction of root mean square error and relative RMSE, respectively